The County of Los Angeles Department of Public Works is committed to “preserve the long-term well-being and resiliency of our communities and the environment by investing in infrastructure, promoting economically sound, socially desirable, and environmentally healthy projects” as stated in our strategic plan. The McDonnell Avenue, Et Al project, completed in September of 2017, was an outstanding example of this commitment as it used many sustainable design elements to improve numerous local roads within the unincorporated community of East Los Angeles. Several sustainable pavement reconstruction treatments were used that recycle the existing material and/or use recycled material making this project both cost effective as well as beneficial to the environment in comparison to the traditional remove and replace with new materials methods. The structural section was composed of 1 ½ inches of Asphalt Rubber Hot Mix (ARHM) on 3 inches of Cold Central Plant Recycled Asphalt Concrete Pavement (CCPRACP) on 8 inches of Cement Stabilized Pulverized Base (CSPB). ARHM, used as the top layer, is composed of recycled rubber repurposed from old tires. It provides a quieter surface ideal for residential areas, resists cracking, and has a longer life cycle with virtually no maintenance. CCPRACP restores the existing asphalt by mixing it with recycling agents, eliminating the use of new asphalt and aggregates. CSPB improves the strength and stability of the existing base by adding small percentage of Portland cement. Since CSPB is processed on site, this pulverization procedure eliminates the need to export excavated materials or import of new base material. By using the pavement treatments mentioned above, there was a reduction of 53 percent in greenhouse gas emissions and a reduction of 61 percent in energy consumption. This led to a cost saving of $1,784,000. These treatments also saved approximately 16,000 cubic yards of materials from being dumped into our landfills. In addition to the sustainable pavement treatments, several low impact development features such as stormwater bioretention filtration basins were constructed to improve water quality. These basins collect rain and nuisance water before it enters the storm drain system. The water enters a soil media that removes many of the pollutants and then infiltrates into the ground recharging the groundwater table and improving water quality. Trees are also planted within these basins to absorb the water and pollutants, thus improving the air quality of the community. McDonnell Av, Et Al project improved the community of East Los Angeles by using environmentally friendly and cost-effective methods to reconstruct the pavement and added new features that benefit the environment.
East Los Angeles
City or County Responsible for Project:
Los Angeles County
Roads: Efficient and Sustainable Road Maintenance, Construction and Reconstruction Projects.
Narrative Description Of Your Entry:
Management Specialist II
Los Angeles County Department of Public Works
900 South Fremont Avenue, Alhambra, CA 91803